A video is shown on a screen placed in close proximity to the eyes of a user while the user is wearing a head-mounted display. The user cannot see anything except the displayed video image while wearing the head-mounted display and can therefore enjoy the feeling of unity with a virtual space. Technologies related to the above, disclosed in patent document 1, comprise a video generating method and a video generating device that is capable of detecting the movement of a user and displaying on a head-mounted display an image that corresponds to the user's movements.